3&#39;-(Substituted phenyl)-spiro[isobenzofuran-1(3H),5&#39;(4&#39;H)-isoxazol]-3-ones

ABSTRACT

3&#39;-(Substituted phenyl)-spiro[isobenzofuran-1(3H),5&#39;(4&#39;H)-isoxazol]-3-ones have been found to be effective as herbicides and plant growth regulants, especially for the regulation of soybeans.

This invention relates to compounds useful as herbicides and plantgrowth regulants. The compounds may be represented by the formula##STR1## wherein X and Y are independently selected from the groupconsisting of hydrogen, halogen, lower alkyl, lower alkoxy,halo-lower-alkyl, phenoxy, phenyl and cyano.

The terms "lower alkyl" and "lower alkoxy" as used herein are understoodto include those alkyl and alkoxy groups having up to five carbon atoms,inclusive. Both straight as well as branched chain alkyl groups arecontemplated.

The term "halo-lower-alkyl" as used herein is understood to mean thoselower alkyl groups in which at least one, and perhaps all, of thehydrogen atoms have been replaced by halogen atoms. It is to be clearlyunderstood that trifluoromethyl is contemplated as being ahalo-lower-alkyl moiety.

The term "halogen" as used herein includes chlorine, bromine, fluorineand iodine.

In accordance with one of the novel aspects of the present invention,the compounds of the foregoing formula may be prepared by the reactionof the appropriate nitrile oxide with 3-methylenephthalide. The reactionreadily proceeds at room temperature and atmospheric pressure althoughslightly elevated temperatures and pressures may be utilized to increasethe rate of reaction. Although the nitrile oxide may be generatedseparately and then reacted with 3-methylenephthalide, it has been foundto be convenient to generate the nitrile oxide in situ by reacting anappropriate chlorooxime with 3-methylenephthalide under basic conditionsas follows: ##STR2## This reaction proceeds at room temperature andatmospheric pressure although slightly elevated temperatures andpressures may be utilized. Normally, an equimolar ratio of reactants isutilized. When the nitrile oxide is relatively unstable, a large excessof chlorooxime may be utilized. Under most conditions, a slight excessis preferred. The molar ratio to be utilized with any given reaction iswithin the skill of the art. As noted, the reaction proceeds under basicconditions. Bases such as tertiary amines are preferred. Especiallypreferred is the use of a stoichiometric amount of triethylamine. Anyinert solvent in which the reactants are readily soluble may beutitlized. These include ether, dimethylformamide, tetrahydrofuran,chloroform, carbon tetrachloride, methylene chloride, dioxane and thelike.

Chlorooximes are known in the art and are readily prepared by reactionof hydroxylamine with the appropriate aryl aldehyde in aqueous alcohol,followed by chlorination of the resultant oxime in accordance with thefollowing scheme: ##STR3##

Aryl aldehydes may be prepared by the procedure of Jolad and Rajagopal,Org. Syn. Coll., Vol. V, Page 139 (1973). The procedure of S. V.Vinogradova et al, J. Appl. Chem. (USSR), 44, 1405 (1971) may be used toprepare 3-methylenephthalide. In order to illustrate the aboveprocedure, the following examples are presented. These examples aremerely illustrative and are not intended as a limitation on the scope ofthe invention.

EXAMPLE 1 Preparation of3'-(3-Biphenylyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

To a solution of 4-biphenylylcarboxaldehyde chlorooxime (34.8 g, 0.15mole) and 3-methylenephthalide (14.6 g, 0.1 mole) in 450 ml. of etherwas added dropwise triethylamine (15.18 g, 0.15 mole) at 5° C. in 20minutes. The resultant mixture was stirred at room temperature for 20hours. The solid was then filtered off. The ethereal solution containeda very small amount of the desired spiro compound according to an NMRanalysis. The solid material which was filtered off from the originalether solution was extracted twice with 1200 ml. of chloroform. Thechloroform solution was washed twice with water, dried over CaSO₄ andconcentrated under vacuum to give 24.7 g (72.4%) of a beige solid; m.p.152°-159° C. with decomposition. Recrystallization of 3.5 g of the beigesolid from 100 ml. of chloroform gave 1.47 g of white solid; m.p.170°-172° C. with decomposition.

Anal. Calc'd. for C₂₂ H₁₅ NO₃ : C, 77.41; H, 4.43. Found: C, 77.36; H,4.45.

EXAMPLE 2 Preparation of3'-(4-Chlorophenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

To a solution of 17 g (0.089 mole) of p-chlorobenzaldehyde chlorooximeand 14.0 g (0.096 mole) 3-methylenephthalide in 300 ml. of ether wasadded 9.0 g (0.089 mole) of triethylamine in 50 ml. of ether at 0°-5° C.during 1 hour. The solution was then allowed to react at roomtemperature for 20 hours. An infrared spectrum of an aliquot indicatedthat the reaction was complete. The solid was filtered off. The etherealsolution was washed three times with sodium chloride saturated water,dried over CaSO₄ and concentrated under vacuum. Only 2 g of impureproduct was obtained. The solid material which was filtered off from theoriginal solution was added to 500 ml. of chloroform and washed threetimes with water. The chloroform solution was cloudy even after 200 ml.of tetrahydrofuran had been added. The chloroform- tetrahydrofuransolution was then dried over CaSO₄, filtered and concentrated undervacuum to afford 10.2 g of pale yellow solid (38.2%), m.p. 158°-160° C.A colorless solid, m.p. 166°-167° C., was obtained after several washeswith ether.

Anal. Calc'd. for C₁₆ H₁₀ NClO₃ : C, 64.12; H, 3.36; N, 4.67; Cl, 11.83.Found: C, 64.14; H, 3.37; N, 4.67; Cl, 11.81.

EXAMPLE 3 Preparation of3'(2-Methylphenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

To a solution of o-tolualdehyde chlorooxime (26.8 g, 0.158 mole),3-methylenephthalide (14.6 g, 0.1 mole) and ether (400 ml.) was addeddropwise a solution of triethylamine (16 g, 0.158 mole) in 30 ml. ofether at 5°-10° C. in 45 minutes. The mixture was stirred at roomtemperature for 40 hours and filtered. The solid material collected wasdissolved in 1 liter of chloroform and 200 ml. of water. The chloroformsolution was then washed two times with water, dried over CaSO₄ andconcentrated under vacuum to give 16.4 g of white solid, m.p. 146°-149°C. The original ether solution was washed two times with water, driedover CaSO₄ and concentrated to 100 ml. Another 1.64 g of the spirocompound precipitated out. The ether solution was then furtherconcentrated to 10.8 g of yellow-brown oil which did not contain asignificant amount of the desired product. Recrystallization of 12 g ofthe crude spiro compound from tetrahydrofuran-ether gave 9.87 g of apure white solid, m.p. 159°-164° C. with decomposition.

Anal. Calc'd. for C₁₇ H₁₃ NO₃ : C, 73.11; H, 4.69. Found: C, 73.06; H,4.74.

EXAMPLE 4 Preparation of3'-(3-Cyanophenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(3-Cyanophenyl)-spiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-one wasprepared according to the procedure of Example 3 in 62.7% isolatedyield. The spiro compound obtained was a white solid, m.p. 134°-137° C.Recrystallization of 12 g of crude spiro compound fromtetrahydrofuran-toluene afforded 6.48 g of white solid, m.p. 165°-167°C.

Anal. Calc'd. for C₁₇ H₁₀ N₂ O₃ : C, 70.34; H, 3.67. Found: C, 70.07; H,3.50.

EXAMPLE 5 Preparation of3'-(4-Trifluoromethylphenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(4-trifluoromethylphenyl)-spiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-onewas prepared according to the procedure of Example 3 in 36.8% isolatedyield. Recrystallization of 5 g of the crude spiro product from 75 ml.of tetrahydrofuran and 50 ml. of ether gave 3.83 g of pure product aswhite crystals, m.p. 177°-178° C.

Anal. Calc'd. for C₁₇ H₁₀ F₃ NO₃ : C, 61.27; H, 3.02. Found: C, 61.29;H, 3.06.

EXAMPLE 6 Preparation of3'-(2-Trifluoromethylphenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(2-trifluoromethylphenyl)-spiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-onewas prepared in 35.2% isolated yield according to the procedure ofExample 3. The crude spiro product obtained was a white solid, m.p.149°-150.5° C. Recrystallization of 5 g of the solid fromtetrahydrofuran (50 ml.) and ether (50 ml.) afforded 4.12 g of colorlessneedles, m.p. 156°-157.5° C.

Anal. Calc'd. for C₁₇ H₁₀ F₃ NO₃ : C, 61.27; H, 3.02. Found: C, 61.24;H, 3.05.

EXAMPLE 7 Preparation of3'-(3-Methoxyphenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(3-methoxyphenyl)spiro[isobenzofuran-1(3H),5'(4'H)-isoxaol]-3-one wasprepared following the procedure of Example 3. The original ethersolution was washed two times with water, dried over CaSO₄ andconcentrated to 29.6 g of thick oil. The oil contained 50% of the spiroproduct according to NMR analysis. Isolation of the spiro compound fromthe oil was not attempted. The solid material which was filtered offfrom the original ether solution afforded after workup, 5.56 g (18.8%yield) of the desired product as a yellow solid, m.p. 119.5°-123° C.Recrystallization of the solid from tetrahydrofuran-ether gave 4.3 g ofa pale yellow solid, m.p. 124°-126° C. with decomposition.

Anal. Calc'd. for C₁₇ H₁₃ NO₄ : C, 69.15; H, 4.44. Found: C, 69.03; H,4.50.

EXAMPLE 8 Preparation of3'-(3-Phenoxyphenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(3-phenoxyphenyl)-spiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-onewas prepared in 53.9% isolated yield according to the procedure ofExample 3. The crude spiro compound isolated was a yellow oil.Purification of 7.9 g of the oil by high pressure liquid chromatographyon silica gel with 50% ethyl acetate--50% hexane as the eluant gave 4.2g of the desired product as a white solid, m.p. 114°-116° C.

EXAMPLE 9 Preparation of3'-(3-Chlorophenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(3-chlorophenylspiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-one wasprepared in 86.4% isolated yield according to the procedure of Example3. The crude product was a gummy material. Recrystallization of 19 g ofthe gummy material from tetrahyrofuranether gave 5.2 g of solid, m.p.119°-125° C. A sample of 3.5 g of the solid was purified further by highpressure liquid chromatography on a silica gel column with 50% hexane -50% ethyl acetate as eluant to give 1.77 g of the desired product as awhite solid, m.p. 127°-129° C.

Anal. Calc'd. for C₁₆ H₁₀ ClNO₃ : C, 64.12; H, 3.36. Found: C, 63.88; H,3.40.

EXAMPLE 10 Preparation of3'(2,4-Dichlorophenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

By a method similar to the procedure of Example 2, a reaction of2,4-dichlorobenzaldehyde chlorooxime and 3-methylenephthalide wascarried out. The solid collected from the reaction mixture afforded 12.2g of the desired product after workup, and the ether solution gave 4 gof the desired product (yield 70.2%). Recrystallization from chloroformled to pure white crystals of the desired product, m.p. 158°-161° C.

Anal. Calc'd. for C₁₈ H₁₃ NCl₂ O₃ : C, 57.86; H, 2.73. Found: C, 57.63;H, 2.74.

EXAMPLE 11 Preparation of 3'-Phenyl-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One. 3'-Phenyl-spiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-one ws prepared according to the procedure ofExample 2 in 30% isolated yield, m.p. 103°-106° C.

Anal. Calc'd. for C₁₆ H₁₁ NO₃ : C, 72.45; H, 4.18. Found: C, 72.39; H,4.21.

EXAMPLE 12 Preparation of3'-(3-Trifluoromethylphenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

To a solution of 109.5 g (0.75 mole) of 3-methylenephthalide and 285 g(1.27 mole) of m-trifluoromethylbenzaldehyde chlorooxime in 3.5 litersof ether was added 128.3 g (1.27 mole) of triethylamine in 250 ml. ofether at 0° C. during 3 hours. The solution was then stirred at roomtemperature overnight. An infrared spectrum indicated that the reactionwas complete. The solid was filtered off. The ethereal solution waswashed once with 10% HCl, twice with sodium chloride saturated water,dried over CaSO₄ and concentrated under vacuum. Only 19.5 g of impureproduct was obtained. The solid material which was filtrated from theoriginal reaction solution was stirred with 4 liters of tetrahydrofuranfor 4 hours and filtered through a Buchner funnel. The tetrahydrofuransolution obtained was washed once with 10% HCl solution and twice withwater saturated with sodium chloride. After being dried andconcentrated, the tetrahydrofuran solution gave 140.6 g of pure product,m.p. 170° C.

Anal. Calc'd for C₁₇ H₁₀ F₃ NO₃ : C, 61.27; H, 3.02. Found: C, 61.25; H,3.04.

EXAMPLE 13 Preparation of3'-(p-Fluorophenyl)-Spiro[Isobenzofuran-1(3H),5'(4'H)-Isoxazol]-3-One.

3'-(p-fluorophenyl)-spiro[isobenzofuran-1(3H),5'(4'H)-isoxazol]-3-onewas prepared according to the procedure of Example 1 in 65% isolatedyield, m.p. 142°-145° C.

Anal. Calc'd. for C₁₆ H₁₀ FNO₃ : C, 67.84; F, 3.56. Found: C, 67.89; F,3.59.

In accordance with one aspect of the present invention, the spirocompounds of the foregoing formula have been found to be effective asherbicides. The compounds may be used by themselves or as the activeingredient in a herbicidal composition.

As used herein, the term "herbicidal active ingredient" is understood tomean a spiro compound of the foregoing formula (I).

Control of undesirable weed growth may be obtained by applying theherbicidal active ingredient to the plant locus which is defined hereinto include the growth medium surrounding the plant, the seeds, emergingseedlings, roots, stems, leaves, flowers and other plant parts.

To illustrate the herbicidal properties of the compounds of the presentinvention, said compounds were tested in the following manner.

The pre-emergent test was conducted as follows:

A good grade of top soil was placed in aluminum pans and compacted to adepth of 0.95 to 1.27 cm. from the top of the pan. On the top of thesoil was placed a predetermined number of seeds or vegetative propagulesof various plant species which are compacted to a soil level. The soilrequired to level fill the pans after seeding or adding vegetativepropagules was weighed into a pan. A known amount of the herbicidalactive ingredient applied in a solvent or as a wettable powder and thesoil were thoroughly mixed, and used as a cover layer for prepared pans.After treatment, the pans were moved into a greenhouse bench where theywere watered from below as needed to give adequate moisture forgermination and growth.

As noted in Tables I and II, below, approximately 2 or 4 weeks afterseeding and treating, the plants were observed to determine alldeviations from the normal growth habit and the results recorded. Aherbicidal rating code was used to signify the extent of phytotoxicityof each species. The ratings are defined as follows:

    ______________________________________                                               % Control      Rating                                                  ______________________________________                                               0-24           0                                                              25-49          1                                                              50-74          2                                                              75-100         3                                                       ______________________________________                                    

The plant species utilized in these tests are identified by letter inaccordance with the following legend:

A--Canada Thistle

B--Cocklebur

C--Velvetleaf

D--Morningglory

E--Lambsquarters

F--Smartweed

G--Yellow Nutsedge

H--Quackgrass

I--Johnsongrass

J--Downy Brome

K--Barnyardgrass

L--Soybean

M--Sugar Beet

N--Wheat

O--Rice

P--Sorghum

Q--Wild Buckwheat

R--Hemp Sesbania

S--Panicum Spp

T--Crabgrass

Results of the pre-emergent tests are summarized in Tables I and II,below.

                                      TABLE I                                     __________________________________________________________________________                    Pre-Emergent                                                  Compound of kg  Plant Species                                                 Example No.                                                                          WAT* h   A B C D E F G H I J K                                         __________________________________________________________________________    1      2    11.2                                                                              0 0 0 2 1 2 0 0 0 1 3                                         2      4    11.2                                                                              3 2 3 3 3 3 2 3 0 1 3                                         3      4    11.2                                                                              3 2 3 3 3 2 3 3 0 2 2                                         4      4    11.2                                                                              1 1 3 3 2 2 1 2 0 2 1                                         5      2    11.2                                                                              0 0 1 1 2 3 0 2 0 1 2                                         6      4    11.2                                                                              3 2 2 2 2 2 2 2 0 2 3                                         7      4    11.2                                                                              3 1 2 3 3 3 2 2 0 2 3                                         8      4    11.2                                                                              3 --                                                                              1 1 3 3 0 0 0 0 3                                         9      4    11.2                                                                              3 1 2 3 3 1 2 3 1 3 3                                         10     4    11.2                                                                              0 0 1 --                                                                              2 1 0 1 0 2 2                                         11     4    11.2                                                                              3 2 3 3 3 2 1 2 1 1 3                                         12     4    11.2                                                                              3 2 3 3 3 3 2 3 0 2 3                                         13     4    11.2                                                                              2 --                                                                              2 2 2 2 0 3 2 1 3                                         __________________________________________________________________________     *--Weeks after treatment.                                                

                                      Table II                                    __________________________________________________________________________                  Pre-Emergent                                                    Compound of                                                                              kg Plant Species                                                   Example No.                                                                          WAT*                                                                              h  L M N O P B Q D R E F C J S K T                                 __________________________________________________________________________    1      2   5.6                                                                              0 1 0 1 1 0 0 1 3 3 3 0 2 0 3 3                                 1      2   1.12                                                                             0 0 0 0 0 0 0 1 2 3 1 0 0 0 2 2                                 2      4   5.6                                                                              1 2 1 2 2 1 1 2 1 --                                                                              3 2 1 0 3 0                                 2      2   1.12                                                                             0 2 0 1 0 0 0 2 0 --                                                                              0 0 1 0 0 0                                 2      2   0.28                                                                             0 2 0 0 0 0 0 0 0 --                                                                              0 0 0 0 0 0                                 3      4   5.6                                                                              0 3 3 2 2 1 0 0 1 3 2 3 3 3 3 3                                 3      4   1.12                                                                             0 2 2 1 1 1 1 2 0 3 0 2 2 2 2 2                                 3      2   0.28                                                                             1 2 1 1 0 0 1 0 0 3 1 0 0 0 1 2                                 4      4   5.6                                                                              1 3 1 2 2 0 3 1 3 3 3 2 0 1 1 3                                 4      2   1.12                                                                             1 3 0 0 0 0 2 0 1 3 1 1 0 0 1 1                                 4      2   0.28                                                                             0 1 0 0 0 0 0 0 0 2 0 0 0 0 0 1                                 5      4   5.6                                                                              2 3 1 1 2 0 3 1 2 3 3 1 1 0 3 1                                 5      2   1.12                                                                             0 1 0 1 0 0 2 0 0 3 3 0 0 0 0 3                                 6      4   5.6                                                                              1 2 0 1 0 1 2 0 1 2 3 1 0 1 2 3                                 6      4   1.12                                                                             0 2 0 2 1 0 1 1 2 2 3 0 3 0 2 3                                 6      2   0.28                                                                             0 1 0 1 0 0 1 1 0 0 1 0 0 0 1 1                                 7      4   5.6                                                                              3 3 2 3 2 2 2 2 2 2 3 2 2 2 3 3                                 7      4   1.12                                                                             0 2 0 0 0 0 0 2 0 0 0 1 3 0 0 0                                 7      2   0.28                                                                             0 1 0 0 0 0 0 0 1 0 2 0 1 0 0 2                                 7      2   0.056                                                                            0 1 0 0 0 0 0 0 0 1 1 0 0 0 0 1                                 8      2   5.6                                                                              0 1 0 0 0 3 2 3 2 3 0 0 0 0 3 2                                 8      2   1.12                                                                             0 1 0 0 0 --                                                                              1 3 0 1 1 1 0 0 3 2                                 8      2   0.28                                                                             3 1 0 0 0 3 0 0 0 1 1 0 0 0 2 2                                 9      4   5.6                                                                              3 3 1 3 2 1 2 2 3 3 2 3 2 3 3 3                                 9      4   1.12                                                                             1 3 0 1 0 0 3 3 2 3 3 1 0 0 0 1                                 9      4   0.28                                                                             0 2 0 2 0 0 0 3 1 2 3 2 2 2 2 3                                 10     2   5.6                                                                              1 3 1 2 1 --                                                                              0 0 1 3 3 2 1 1 2 3                                 10     2   1.12                                                                             1 2 0 2 0 --                                                                              0 0 1 3 1 0 1 1 3 1                                 10     2   0.28                                                                             0 2 0 2 0 --                                                                              0 --                                                                              0 2 1 0 1 0 1 2                                 11     4   5.6                                                                              2 3 0 2 1 0 0 3 3 3 2 2 0 1 3 1                                 11     4   1.12                                                                             0 3 0 1 0 0 0 2 3 3 3 2 0 0 1 0                                 11     2   0.28                                                                             0 0 0 1 0 0 1 1 3 1 1 1 0 0 0 1                                 12     4   5.6                                                                              3 3 1 3 2 1 3 3 3 3 3 2 1 2 3 3                                 12     4   1.12                                                                             2 3 0 3 1 1 3 2 3 3 2 2 0 0 2 3                                 12     2   0.28                                                                             3 1 0 1 1 1 1 2 3 3 1 2 0 0 1 3                                 13     4   5.6                                                                              2 3 1 2 3 --                                                                              3 1 3 3 3 1 1 0 3 3                                 13     4   1.12                                                                             1 2 1 1 2 --                                                                              0 --                                                                              1 0 0 1 0 1 1 1                                 13     2   0.28                                                                             1 1 0 0 0 --                                                                              0 0 0 1 1 0 0 0 0 0                                 __________________________________________________________________________     *--Weeks after treatment.                                                

The post-emergent tests were conducted as follows:

The herbicidal active ingredients are applied in spray form to two orthree-week old specimens of various plant species. The spray, a solutionor wettable powder suspension containing the appropriate rate ofherbicidal active ingredient to give the desired test rate and asurfactant, is applied to the plants. The treated plants are placed in agreenhouse and approximately two or four weeks later the effects areobserved and recorded. The results are shown in Tables III and IV inwhich the post-emergent herbicidal rating code is as follows:

    ______________________________________                                               % Control      Rating                                                  ______________________________________                                                0-24          0                                                              25-49          1                                                              50-74          2                                                              75-99          3                                                              100            4                                                       ______________________________________                                    

The plant species utilized in these tests are identified by letter inaccordance with the previous legend.

                                      Table III                                   __________________________________________________________________________                   Post Emergent                                                  Compound of                                                                              kg  Plant Species                                                  Example No.                                                                          WAT*                                                                              h   A B C D E F G H I J K                                          __________________________________________________________________________    1      2   11.2                                                                              0 1 0 1 1 0 0 0 0 0 0                                          2      4   11.2                                                                              1 2 1 1 --                                                                              0 0 0 0 0 0                                          3      4   11.2                                                                              2 1 1 1 1 2 1 0 1 1 2                                          4      4   11.2                                                                              1 1 1 1 1 0 0 0 0 0 0                                          5      2   11.2                                                                              1 0 1 1 1 1 0 0 0 0 0                                          6      4   11.2                                                                              1 2 1 2 1 1 0 0 0 0 0                                          7      4   11.2                                                                              1 2 2 2 1 3 1 0 0 0 2                                          8      4   11.2                                                                              1 2 1 2 2 2 0 0 0 0 0                                          9      4   11.2                                                                              4 2 2 1 2 4 1 0 2 1 1                                          10     4   11.2                                                                              1 1 1 1 1 0 1 0 0 0 0                                          11     4   11.2                                                                              2 2 2 2 2 3 1 1 1 1 1                                          12     4   11.2                                                                              2 2 2 3 2 4 2 2 1 0 2                                          13     4   11.2                                                                              2 2 2 2 2 1 0 0 2 0 1                                          __________________________________________________________________________      *--Weeks after treatment.                                               

                                      Table IV                                    __________________________________________________________________________                  Post Emergent                                                   Compound of                                                                              kg Plant Species                                                   Example No.                                                                          WAT*                                                                              h  L M N O P B Q D R E F C J S K T                                 __________________________________________________________________________    7      4   5.6                                                                              2 --                                                                              1 0 0 2 2 2 2 1 4 2 1 0 1 0                                 7      2   1.12                                                                             2 1 0 0 0 2 2 2 2 1 3 2 0 1 1 1                                 7      2   0.28                                                                             1 --                                                                              0 0 0 1 1 1 1 1 2 1 0 0 1 0                                 9      4   5.6                                                                              2 2 1 1 2 2 4 2 4 3 4 2 1 1 2 1                                 9      4   1.12                                                                             2 1 0 1 0 2 2 2 2 2 4 2 0 0 1 0                                 9      2   0.056                                                                            0 1 0 1 0 0 0 0 0 3 2 0 1 0 0 1                                 11     4   5.6                                                                              2 2 1 0 2 2 2 2 --                                                                              4 4 2 1 0 1 2                                 11     4   1.12                                                                             2 1 0 0 0 2 --                                                                              2 2 4 2 2 0 1 0                                   12     4   5.6                                                                              2 2 0 1 1 2 3 2 --                                                                              2 --                                                                              2 0 1 2 0                                 12     4   1.12                                                                             2 1 0 0 1 --                                                                              2 2 --                                                                              2 2 2 0 1 2 1                                 12     2   0.056                                                                            0 2 0 0 0 0 2 0 1 1 1 1 0 0 1 2                                 12     2   0.01                                                                             0 0 0 0 0 --                                                                              0 0 0 1 0 0 1 1 0 2                                 __________________________________________________________________________     *--Weeks after treatment.                                                

The above tables illustrate one aspect of the present invention, thatis, the use of the compounds of the invention to kill or injureundesirable plants, e.g., weeds. Another aspect of the invention,however, is the use of the spiro compounds of formula (I) for theregulation of desirable plant growth, especially leguminous plants suchas soybeans. More particularly, it has been found that compounds of theforegoing formula (I) have been found to be effective in regulating thegrowth of leguminous plants.

As used herein, the regulation of "plant growth or development" isunderstood to mean the modification of the normal sequential developmentof a treated desirable plant to agricultural maturity. Suchmodifications are most readily observed as changes in size, shape, coloror texture of the treated plant or any of its parts. Similarly, changesin the quantity of plant fruit or flowers are also quite apparent fromvisual inspection. The above changes may be characterized as anacceleration or retardation of plant growth, stature reduction, leaf orcanopy alteration, increased branching, terminal inhibition, increasedflowering, defoliation, increased root growth, increased cold hardinessand the like. While many of these modifications are desirable in and ofthemselves, most often it is their effect on the economic result that isof most importance. For example, a reduction in stature of the plantpermits the growing of more plants per unit area. A darkening of thefoliar color may be illustrative of higher chlorophyll activityindicative of improved rate of photosynthesis.

Although the regulation of plant growth in accordance with the presentinvention may include partial inhibition of plant growth when used as aplant growth regulant, it does not include the total inhibition orkilling of such plants. The present invention contemplates the use of anamount of the spiro compounds of formula (I) as the active ingredient ina plant growth regulating composition which will modify the normalsequential development of the treated plant to agricultural maturity.Such plant growth regulating amounts may vary, not only with thematerial selected, but also with the modifying effect desired, thespecies of plant and its stage of development, the plant growth mediumand whether a permanent or a transitory effect is sought. It is,however, well within the skill of the art to determine the amount ofactive ingredient required.

Modification of the plants may be accomplished by applying the activeingredient to the plant locus which has been defined herein to includethe growth medium surrounding the plant, the seeds, emerging seedlings,roots, stems, leaves, flowers, or other plant parts. Such applicationmay be made directly to the plant part, or indirectly by application tothe plant growth medium.

Utilizing the spiro compounds of formula (I) as the active ingredient ina plant growth regulating composition, said compounds were found topossess plant growth regulating activity when tested in accordance withthe following procedure.

A number of soybean plants, variety Williams, were grown from seeds inplastic pots in the greenhouse for a period of one week at which timethe plants are thinned to one plant per pot. When the second trifoliateleaf (three weeks) was fully expanded, the plants were treated with asolution of the active ingredient in acetone and water. Aqueous Tween 20was used as a surfactant.

When the fifth trifoliate leaf (four to five weeks) was fully expanded,the treated plants were compared with the non-treated control plants andthe observations recorded. Those observations are summarized in Table Vbelow.

                  Table V                                                         ______________________________________                                        Compound of                                                                            Rate                                                                 Example No.                                                                            (kg/h)  Observations                                                 ______________________________________                                        1        2.8     Stature reduction, leaf alteration of old                                     and new growth, leaf inhibition, axillary                                     bud inhibition, inhibition of dry weight.                    1        0.56    Stature reduction, leaf alteration of old                                     and new growth, leaf inhibition, axillary                                     bud inhibition, inhibition of dry weight.                    1        0.112   Stature reduction, leaf alteration of old                                     and new growth, leaf inhibition, axillary                                     bud inhibition, inhibition of dry weight.                    2        2.8     Stature reduction, dark foliar color, leaf                                    inhibition, leaf distortion of old and                                        new growth, inhibition of dry weight.                        2        0.56    Stature reduction, dark foliar color, leaf                                    inhibition, leaf distortion of old and                                        new growth, inhibition of dry weight.                        2        0.112   Stature reduction, altered canopy, leaf                                       inhibition, leaf alteration of old and                                        new growth, inhibition of dry weight.                        3        2.8     Stature reduction, altered canopy, leaf                                       inhibition, leaf alteration of old and                                        new growth, inhibition of dry weight.                        3        0.56    Leaf alteration of old and new growth,                                        inhibition of dry weight.                                    3        0.112   Inhibition of dry weight.                                    4        2.8     Stature reduction, inhibition of apical                                       development, leaf inhibition, leaf                                            alteration of new growth, epinasty, inhi-                                     bition of dry weight.                                        4        0.56    Stature reduction, inhibition of apical                                       development, leaf inhibition, leaf                                            alteration of new growth, epinasty, inhi-                                     bition of dry weight.                                        4        0.112   Stature reduction, inhibition of apical                                       development, leaf inhibition, leaf                                            alteration of new growth, epinasty, inhi-                                     bition of dry weight.                                        5        2.8     Stature reduction, leaf inhibition, leaf                                      alteration of old and new growth, epinasty,                                   inhibition of dry weight.                                    5        0.56    Stature reduction, thick leaf texture, leaf                                   alteration of old and new growth, epinasty,                                   inhibition of dry weight.                                    5        0.112   Stature reduction, altered canopy, leaf                                       alteration of old and new growth, epinasty,                                   inhibition of dry weight.                                    6        2.8     Stature reduction, leaf alteration of old                                     and new growth, dark foliar color, leaf                                       inhibition, inhibition of dry weight.                        6        0.56    Stature reduction, leaf alteration of old                                     and new growth, dark foliar color, leaf                                       inhibition, inhibition of dry weight.                        6        0.112   Stature reduction, leaf alteration of old                                     and new growth, leaf inhibition,                                              inhibition of dry weight.                                    7        2.8     Stature reduction, inhibition of apical                                       development, dark foliar color, thick leaf                                    texture, leaf inhibition, inhibition of                                       dry weight.                                                  7        0.56    Stature reduction, inhibition of apical                                       development, dark foliar color, leaf inhi-                                    bition, leaf alteration of new growth,                                        inhibition of dry weight.                                    7        0.112   Stature reduction, inhibition of apical                                       development, leaf inhibition, leaf alter-                                     ation of old and new growth, inhibition                                       of dry weight.                                               8        2.8     Leaf alteration of old and new growth,                                        leaf inhibition, inhibition of dry weight.                   8        0.56    Leaf alteration of old and new growth.                       8        0.112   None                                                         9        2.8     Stature reduction, inhibition of apical                                       development, dark foliar color, thick leaf                                    texture, leaf inhibition, inhibition of                                       dry weight.                                                  9        0.56    Stature reduction, inhibition of apical                                       development, dark foliar color, thick leaf                                    texture, leaf inhibition, inhibition of                                       dry weight.                                                  9        0.112   Stature reduction, inhibition of apical                                       development, dark foliar color, leaf inhi-                                    bition, leaf alteration of new growth,                                        inhibition of dry weight.                                    10       2.8     Leaf alteration, leaf inhibition.                            10       0.56    Leaf alteration.                                             10       0.112   None.                                                        11       2.8     Stature reduction, inhibition of apical                                       development, dark foliar color, thick leaf                                    texture, leaf inhibition, inhibition of                                       dry weight.                                                  11       0.56    Stature reduction, dark foliar color,                                         thick leaf texture, altered canopy, leaf                                      inhibition, inhibition of dry weight.                        11       0.112   Stature reduction, dark foliar color,                                         thick leaf texture, altered canopy, leaf                                      inhibition, inhibition of dry weight.                        12       2.8     Stature reduction, leaf distortion of                                         new growth, dark foliar color, thick leaf                                     texture, leaf inhibition, inhibition of                                       dry weight.                                                  12       0.56    Stature reduction, leaf distortion of                                         new growth, dark foliar color, thick leaf                                     texture, leaf inhibition, inhibition of                                       dry weight.                                                  12       0.112   Stature reduction, leaf distortion of                                         new growth, dark foliar color, thick leaf                                     texture, leaf inhibition, inhibition of                                       dry weight.                                                  13       2.8     Stature reduction, leaf alteration, leaf                                      inhibition, leaf distortion of new                                            growth, inhibition of dry weight.                            13       0.56    Stature reduction, leaf alteration, leaf                                      inhibition, leaf distortion of new                                            growth, inhibition of dry weight.                            13       0.112   Leaf alteration of old and new growth,                                        leaf inhibition.                                             ______________________________________                                    

As can be seen from the above data, the spiro compounds of the inventionare especially effective in reducing the stature of soybean plants aswell as altering the leaf morphology.

Thus, the above data illustrate that the compounds of the invention maybe used as a herbicide or a plant growth regulant. When used as aherbicide, it is desirable that rates of application about 1.12kilograms per hectare and above be utilized. When used to regulate thegrowth of desirable plants, rates below 5.6 kilograms per hectare,especially 0.056 to 2.8, are preferred.

In selecting the appropriate time and rate of application of the activeingredient, it will be recognized that precise rates will also bedependent upon the desired response, mode of application, plant variety,soil conditions and various other factors known to those skilled in theart. In addition, it will be recognized that single or multipleapplications may be used to exert the desired response.

In the practice of the invention, the active ingredient, whether used asa herbicide or a plant growth regulant, can be used alone or incombination with other pesticides or a material referred to in the artas an adjuvant in either liquid or solid form. To prepare suchcompositions, the active ingredient is admixed with an adjuvantincluding diluents, extenders, carriers and conditioning agents toprovide compositions in the form of finely-divided particulate solids,granules, pellets, wettable powders, dusts, solutions and aqueousdispersions or emulsions. Thus, the active ingredient can be used withan adjuvant such as a finely divided particulate solid, a solvent liquidof organic origin, water, a wetting agent, dispersing agent oremulsifying agent or any suitable combination of these.

Illustrative finely divided solid carriers and extenders which areuseful in the compositions of this invention include the talcs, clays,pumice, silica, diatomaceous earth, quartz, Fullers earth, sulfur,powdered cork, powdered wood, walnut flour, chalk, tobacco dust,charcoal and the like. Typical liquid diluents include Stoddard solvent,acetone, alcohols, glycols, ethyl acetate, benzene and the like. Theplant growth regulating compositions of this invention, particularlyliquids and wettable powders, usually contain one or more surface-activeagents in amounts sufficient to render a given composition readilydispersible in water or in oil. The term "surface-active agent" isunderstood to include wetting agents, dispersing agents, suspendingagents and emulsifying agents. Such surface-active agents are well knownand reference is made to U.S. Pat. No. 2,547,724, columns 3 and 4, fordetailed examples of the same.

Generally, the active ingredients are applied in the form of acomposition containing one or more adjuvants which aid in theapplication of a uniform distribution of the active ingredient. Theapplication of liquid and particulate solid compositions of the activeingredient can be carried out by conventional techniques utilizing, forexample, spreaders, power dusters, boom and hand sprayers and spraydusters. The compositions can also be applied from airplanes as a dustor spray.

Compositions of this invention, whether used as a herbicide or a plantgrowth regulant, generally contain from about 5 to 95 parts activeingredient, about 1 to 50 parts surface-active agent and about 4 to 94parts solvents, all parts being by weight based on the total weight ofthe composition.

Although this invention has been described with respect to specificmodifications, the details thereof are not to be construed aslimitations, for it will be apparent that various equivalents, changesand modifications may be resorted to without departing from the spiritand scope thereof and it is understood that such equivalent embodimentsare intended to be included herein.

What is claimed is:
 1. A compound having the formula ##STR4## wherein Xand Y are independently selected from the group consisting of hydrogen,halogen, lower alkyl, lower alkoxy, halo-lower-alkyl, phenoxy, phenyland cyano.
 2. A compound according to claim 1 wherein X is hydrogen andY is halogen, lower alkyl, lower alkoxy, halo-lower-alkyl, phenoxy,phenyl and cyano.
 3. A compound according to claim 1 wherein saidhalo-lower-alkyl is trifluoromethyl.
 4. A compound according to claim 1wherein Y is halogen.
 5. A compound according to claim 4 wherein Y ischloro.
 6. A compound according to claim 4 wherein Y is fluoro.
 7. Acompound according to claim 1 wherein Y is phenoxy.
 8. A compoundaccording to claim 5 wherein X is hydrogen and Y is chloro in the paraposition.
 9. A compound according to claim 6 wherein X is hydrogen and Yis fluoro in the para position.
 10. A compound according to claim 7wherein X is hydrogen and Y is phenoxy in the meta position.
 11. Acompound according to claim 3 wherein X is hydrogen and Y istrifluoromethyl in the meta position.
 12. A process for preparingcompounds having the formula ##STR5## wherein X and Y are independentlyselected from the group consisting of hydrogen, halogen, lower alkyl,lower alkoxy, halo-lower-alkyl, phenoxy, phenyl and cyano whichcomprises reacting a nitrile oxide having the formula ##STR6## with3-methylenephthalide in an inert solvent.
 13. A process according toclaim 12 wherein said nitrile oxide is prepared in situ by adding achlorooxime having the formula ##STR7## and a base to the3-methylenephthalide solution.
 14. A process according to claim 13wherein said base is a tertiary amine.
 15. A process according to caim14 wherein said amine is triethylamine.
 16. A process according to claim12 which comprises the reaction under basic conditions of a chlorooximehaving the formula ##STR8## with 3-methylene phthalide and a tertiaryamine in an inert solvent.